Traditional data channel transmission techniques include for example, data channel multicasting, which may be employed in a digital subscriber line access multiplexer (DSLAM) network. A DSLAM network provides an end user, at a terminal or other endpoint, with the ability to switch between streams of data, or data channels, received from an upstream source. A DSLAM network is typically designed to accommodate a variety of different types of data channels, such as, for example, a number of video channels as well as channels associated with user data, voice and gaming traffic. The endpoints of a DSLAM platform are customer premises equipment (CPE) devices, which may include, for example, modems at a residence or business and set top boxes (STBs) for terminal equipment (TE) devices, such as televisions. TE devices may also include computers, personal digital assistants (PDAs), telephones or other types of communication terminals. CPE devices include all devices at a customer end, including TE devices. However, for illustrative purposes, TE devices have been distinguished from CPE devices in describing the invention. A DSLAM network enables the delivery of any of the available channels to an end user while simultaneously allowing the end user to use the data, voice and gaming channels.
An end user may select one data channel from a set of channels that are broadcasting at a given time. An Internet group multicast protocol (IGMP) signal has traditionally been used to effect this channel selection by sending an IGMP control message from a CPE device of the end user through the DSLAM network and to a broadband remote access server (B-RAS). The channel selection is conveyed upstream in order to effect the switch to a newly selected channel. In DSLAM applications utilizing a central office (CO), the CO polls for IGMP control messages. A CO may support a large number of CPE devices.
Within the CO, a defined amount of bandwidth is allocated to each modem or end user in a DSLAM network for transmission of selected channels to individual TE devices. When a TE device connected to a modem is turned off, the unused or residual bandwidth attributed to the modem is not used elsewhere, and thus not allocated to other TE devices of that modem. In order to support multiple channel utilization, traditional solutions allocate a large amount of bandwidth to each modem resulting in significant bandwidth wastage when TE devices are off as well as higher costs in providing data channel multicasting.
Thus, a need remains for a technique that improves channel bandwidth utilization, as well as a technique for using residual bandwidth in the active TE devices of an individual modem or other CPE device.